Internal combustion engine



Filed July 13, 1940 m mh m r O N @N wma/m k @Wwf NIIIIIIJI||H Y Ril'hlllB QW A M AUI C. 1.1%? l NN ,\\w\ $1 EN b, m o4 h $1 @W QN NN QN NN NN QNW Patented Mar. 17, 1942 INTERNAL COMBUSTION ENGINE Carl Voorhies,Detroit, Mich., assignor to Eaton Manufacturing Company, Cleveland,Ohio, a

corporation of Ohio Application July 13, 1940, Serial No. 345,326

Claims.

This invention relates to internal combustion engines generally, andmore particularly, concerns `a novel removable guide supporting thehydraulic, self compensating tappets for operating the valves of suchengines, as well as the control of uid flow providing the operatingsupply of liquid medium forsuch tappets.

Among the objects of this invention is the improvement of the art ofinternal combustion engines, the provision in internal combustionengines having hydraulic self-'compensating tappets for operating thevalves of such engines, of novel removable tappet guide members thereforproviding a directional control to the fluid flow forming the operatingsupply of liquid mediumfor such tappets; the provision in internalcombustion engines having hydraulic self-compensating tappets for thevalves of such engines vin-A cluding tappet guides, as above described,having means for causing precipitation of any foreign matter in theoperating supply of the liquid medium therefor before it enters theinternal mechanism of the hydraulic tappets; the provision in aninternal combustion engine, las Aabove described, of an engine blockhaving a'longitudinally bored portion providing an oil passagewayintercepted by a ,plurality of vertically disposed borings for receptionof a like number of externally grooved and shouldered annular 'tappetguide members removably fixed therein, and which have' oil passagewaystherethrough extended angularly therein below andV above thelongitudinal oil passageway for progressive precipitation of any foreignmatter in fluid flowing therethrough and bleeding fluid therefrom forthe operating supply of liquid medium for the Fig. 1 is a verticalsectional. view through a portion of an internal combustion Iengineblock adjacent the valve operating mechanism thereof illustrating apreferred embodiment of this invention; and v Fig. 2 is a sectional endelevation thereof.

Referring now particularly 'to the drawing it will be noted that thereisillustrated fragmen- `tarily an engine block 5 havingl a camshaft 6provided with a plurality of cams 1y equal in number to the valves to beoperated, the` stems 8 of which are fragmentarlly illustrated. Theengine block 5 is provided with a plurality of ver. tically disposedborlngs I0, ina common plane between the valve stems 8 Vandtheunderlying cams 1, and like in number thereto. These bor- .ings I0 arefor reception'of the tappet guide` bushings, generally designated Il,and are intercepted diametrically by a longitudinally extending boringI2 through the block 5.the forward end of which is arranged to besupplied with oil from the usual oil pump of the engine, not

hydraulic tappets received in said tappet guide,

respectively; the provision in an internal combustion engine with ahydraulic tappet guide assembly, as above described, of a plurality oftappet guides assembled in like manner in thedirection of theiroperating fluid ow and the final tappet guide member inserted in reverserelation .continuous fluid lrflow therebeyond metered by the body ofsaid tappetmember.

. tothe preceedingmembers so as to provide a` Further and otherobjects'and advantages of the invention reside in the* novel combinationand arrangement of parts to be hereinafter described, in conjunctionwith the drawing forming a part of this specification, and` pointed outwith vparticularity in the -appended claims.

Inthe drawing like reference characters deand in which:`

shown, and the rear end being closed by a plug I3.

The guide bushings II consist of annular shouldered sleeve-like membersarranged to seat in the borings III and are fixed against .rotation anddisplacement by any suitable means, not shown. Around the outerperiphery of the bushing is a grooved oil passageway I4 which providescontinuous communication -for the longitudinal boring I2 around theguide bushings Il which intercept the same. Oil passageways I5 and I6extend from`the outer peripheral groove I4, of

the tappet guide bushings Il, in a generally ini clined direction belowand above the plane f the longitudinal oil passageway I2, respectively,to the hollow interior bore- I'l of the guides.

Hydraulic self compensating tappet members, generally designated 20, arereceived in the bores Il of the tappet guides, being interposed betweenthe cams 1 and the valve stems 8. 'Ihe particu- ,lar tappets shown areof the mushroom type having a tappet body 2l with a shoe portion 22thereof contacting the cam l; although the tappets might equally as wellbe of the barrel Atype wherein the outer diameter of the tappet body isuniform throughout its lengthand has a hardened cam contacting lowerend. The tappet constructions herein illustrated form no part of thisinvention, being completely described, and claimed in my issued UnitedStates Letters Patent No.

2,074,034, of March- 16, 1937, for Tappet construc-v tion, and for thepurposes of this invention onlyI so much detail as is necessary to thecomplete understanding thereof will'be offered, as reference may be madeto the aforementioned patent for a complete description of the operationthereof. The tappet body 2| has a circumferential groove or recessapproximately mid-way of its length and of such extent that it is always5 in communication with the oil supply passageway I6 during thereciprocation of the tappet 20. One or more apertures 26 extend from thegroove 25 to the hollow interior or oil supply reservoir 21 of thetappet body 2l.

'I'he upper end of the hollow bore of the tappet body is shouldered andadapted to receive a hydraulic self-compensating insert unit 29comprising a separate cylinder, a plunger reciprocable therein, and aplunger spring yieldingly l5 maintaining the plunger off of the bottomof the separate cylinder. A one-way check valve andV its surroundingcage is fitted in the bottom of the separate cylinder, and dependingtherefrom is a suction tube 30 which extends deep down 20 into the oilreservoir 21 in the lower end of the tappet body 2l, For purposes ofthis disclosure it will be. understood that, with the oil reservoir 2'1in the tappet body filled lwith oil, upon reciprocation of the camshaft5 in its valve seating 25 cycle, when the base circle of the cam ispresented to the tappet shoe 22 the plunger spring will tend to urge theassociated plunger outward of the tappet body creating a suction effectin the lower end of the separate cylinder above the 30- check valve, andthereby unseating the same and drawing oil through the suction tube 30from the oil reservoir 21. Duringthe valve lifting cycle of thecamshaft, by the, cam 1, the oil drawn around the unseated check valvewill be trapped thereabove as the check valve is forced onto its seat.It will thus be apparent this cycle is repeated as long as there is anylash in the valve gear to be taken up orcompensated for, until a zeroclearance is maintained therein.

The particular importance of this invention arises from the fact,that inthe operation of such hydraulic self-compensating tappets the supply offluid provided therefor is obtained from the sump or crankcase of theconventional lubricat- .l5 ing system of 'the internal combustionengine, and in mechanisms of this character any foreign matter in thefluid supplied thereto is objectionable. Accordingly, the fluid supplyis introduced under pressure to the longitudinal passageway I2 at theleft hand side of Fig. l, and flows in the direction of the arrowsshown. 'This direction of fluid flow is assumed merely for-purposes ofillustration in conjunction with the concrete embodiment of theinvention disclosed so as to picture the relative relationship of theparts. That is to say, in conjunction with the fragmentary blockshowing, it will be assumed the left hand tappet guide bushing of Fig. 1is the next to the last one and the right-hand tappet guide G0 bushingII is the last one in the path of fluid flow along the longitudinalpassageway I2. The path followed by the pressure fluid then will bethrough the boring I2 around the left hand tappet guide bushing II. andback into the passageway I2 between the tappets. Some entrained' foreignmatter which has been carried by the pressure fluid, being heavier, willbe precipitated down the inclined oil passage I5 and metered out by thetappet body 2l masking the outlet 70 thereof into the valve chamber orback to the engine sump, as the case may be. The major portion of thefluid flow, as aforementioned, continues around the peripheral grooveI4' of the guide bushing to a continuation of the passageway I2 betweenthe two tappets shown. From here the pressured fluid is forced up theinclined oil channel I6 where the tappet body peripheral groove orrecess 25 is in communication with the outlet therefrom during allphases of the reciprocation of the tappet, or intermittent registrationas required; and from when the fluid flows into the aperture 26 to thetappet body oil reservoir 21. Incidentally the uphill climb of the oiland the reservoir also act as a settling medium for any heavy foreignparticles which have not been so far precipitated from the oil line.

At the last tappet on the line of the longitudinal passageway I2, theright hand tappet of Fig. 1, it will be noted the tappet guide bushing II has been reversed or rotated with respect to the preceding members. Inthis arrangement instead of the pressure fluid dead ending here 'andforming a potential sludge pocket there is provided a continuous fluidow by the oil being metered past. the tappet body baiiling the outlet.of the downwardly inclined passage I5 backto the valve chamber or oilsump. The invention is equally as well adapted for radial aircraftengines only in that instance instead of the straight longitudinalpassageway I2 -there would be a circumferentially extending oil channeland suitably inclined oil passages through each of the tappet guidebushings I I.

From the foregoing disclosures it will be apparent there has beendescribed a novel tappet guide bushing and assembly for internalcombustion engines providing a unique directional fluid flow for theoperating supply of the hydraulic selfcompensating tappets thereof,among other things the objectsv and advantages of the invention firstenumerated. It is to be understood, however, the specific embodimentherein illustrated is fo'r purposes of illustration only, and all formalmodifications thereof are intended to be covered within a fairinterpretation of the scope and substance of the invention as defined bythe following claims.

What I claim is:

l. In an internal combustion engine, the combination with a plurality ofhydraulic valve tappets, of an engine block having a wall provided witha like number of cylindrical tappet guide bores having tappet guidebushings therein for receiving said tappets, said tappet guide bores andbushings having their axes extending in substantially the same directionand lying in a common plane, alined passages extending within the wall,between consecutive bores and to the outside of the engine block andjoining with circumferential passages surrounding said guide bushings. asource of liquid supply, a pump arranged between and communicating withsaid source of liquid supply and one end of said 'alined passages forfurnishing liquid thereto, and liquid passages in said guide bushingsextending upwardly and downwardly from said circumferential passages forfurnishing liquid to said tappets and tending to eliminate foreignmatter fromv the alined passages, respectively. l

2. In an internal combustion engine, the combination with a plurality ofhydraulic valve tappets, of an engine block having a wall provided witha like number of cylindrical tappet guide bores having tappet guidebushings therein for receiving said tappets, said tappet guide bores andbushings having their axes extending in substantially the same directionand lying in a common plane, alined passages extending within the wall,between consecutive bores and to the accomplishing outside of the engineblock and joining with circumferential passages surrounding said guidebushings, a source of liquid supply, a pump arranged between andcommunicating with said source of liquid supply and one end of saidalined passages, liquid passages in said guide bushings extendingupwardly and downwardly from said circumferential passages forfurnishing liquid to said tappets and tending to eliminate foreignmatter from the alined passages, respectively, and said tappet guidebushing on the other end of said alined passages being assembled inreverse relation to said other preceding bushings whereby the oilpassages therein are arranged to furnish liquid upwardly to said tappetand to meter liquid downwardly around the body of said tappet,respectively, back to said source of liquid supply for continuouscirculation thereof.

3. In an internal combustion engine, the combination with a plurality ofhydraulic valve tappets, of an engine block having a wall provided witha like number of cylindrical tappet guide bores having tappet guidebushings therein for receiving said tappets, said tappet guide bores andbushings having their axes extending in substantially the same directionand lying in a common plane, alined passages extending within the wall,between consecutive bores and to the outside cf the engine block andjoining with circumferentialpassages surrounding said guide bushings, asource of liquid supply, a pump arranged between and communicating withsaid source of liquid supply and one end of said alined passages, andinclined liquid passages in said guide bushings extending upwardly anddownwardlyfrom said circumferential passages tending to eliminateentrained foreign matter from said liquid supply and to furnish liquidto said tappets, respectively, and in chronological order at eachtappet.

4. In an internal combustion engine, the combination with a plurality ofhydraulic valve tappets of an engine block having a Wall provided with alike number of cylindrical tappet guide bores having tappet guidebushings therein for receiving said tappets, said .tappet guide boresand bushings having their axes extending in subx tending upwardly anddownwardly from said cir-- cumferential passages for furnishingA liquidto said tappets and tending to eliminate foreign matter from the alinedpassages, respectively.

5. In an internal combustion engine, the combination with a plurality ofhydraulic valve tappets, of an engine block provided with a like numberof cylindrical tappet guide bores having their axes extending in thesame general direction in a common plane and adapted to receive saidtappet guides, alined passages extending between consecutive bores andjoining with circumferential passages surrounding said tappet guides,and means for transmission of tappet operating-fluid extending upwardlyand downwardly from said circumferential passages to the tappets, indiametrically opposite sides of the tappet guides, whereby saiddownwardly extending fluid transmission means is on the side presentedto the direction from which the fluid iiows and said upwardly extendinguid transmission means is on the side opposite there- CARL VOORHIES.

